單片機應(yīng)用技術(shù)（經(jīng)典項目化案例式新形態(tài)活頁教材）第5版 課件 p25-2.1 8051的信號引腳

2.18051的信號引腳《單片機應(yīng)用技術(shù)（C語言版）》深圳職業(yè)技術(shù)學(xué)院12345678910111213141516171819204039383736353433323130292827262524232221VCCGND電源引腳接入單片機的工作電源VCC（40）：接+5V電源GND（20）：接地12345678910111213141516171819204039383736353433323130292827262524232221VCCGNDP1.0P1.1P1.2P1.3P1.4P1.5P1.6P1.7P0.0P0.1P0.2P0.3P0.4P0.5P0.6P0.7P3.0P3.1P3.2P3.3P3.4P3.5P3.6P3.7P2.7P2.6P2.5P2.4P2.3P2.2P2.1P2.0P0口（39～32）：P0.0～P0.7引腳P1口（1～8）：P1.0～P1.7引腳P2口（21～28）：P2.0～P2.7引腳P3口（10～17）：P3.0～P3.7引腳12345678910111213141516171819204039383736353433323130292827262524232221VCCGNDP1.0P1.1P1.2P1.3P1.4P1.5P1.6P1.7P0.0P0.1P0.2P0.3P0.4P0.5P0.6P0.7P3.0P3.1P3.2P3.3P3.4P3.5P3.6P3.7P2.7P2.6P2.5P2.4P2.3P2.2P2.1P2.0XTAL2XTAL1RSTRST（9）：Reset，復(fù)位信號XTAL1（19）：片內(nèi)振蕩器的反相放大器和外部時鐘發(fā)生器的輸入端XTAL2（18）：片內(nèi)振蕩器的反相放大器和外部時鐘發(fā)生器的輸出端12345678910111213141516171819204039383736353433323130292827262524232221VCCGNDP1.0P1.1P1.2P1.3P1.4P1.5P1.6P1.7P0.0P0.1P0.2P0.3P0.4P0.5P0.6P0.7P3.0P3.1P3.2P3.3P3.4P3.5P3.6P3.7P2.7P2.6P2.5P2.4P2.3P2.2P2.1P2.0XTAL2XTAL1RSTEAALEPSENPSEN（29）：外部程序存儲器讀選通信號，低電平有效。ALE（30）：地址鎖存控制信號EA（31）：訪問程序存儲控制信號，通常接高電平。引腳名稱引腳功能P0.0～P0.7P0口8位雙向端口線P1.0～P1.7P1口8位雙向端口線P2.0～P2.7P2口8位雙向端口線P3.0～P3.7P3口8位雙向端口線ALE地址鎖存控制信號外部程序存儲器讀選通信號訪問程序存儲控制信號RST復(fù)位信號XTAL1和XTAL2外接晶體引線端VCC＋5V電源VSS地線12345678910111213141516171819204039383736353433323130292827262524232221VCCGNDP1.0P1.1P1.2P1.3P1.4P1.5P1.6P1.7P0.0P0.1P0.2P0.3P0.4P0.5P0.6P0.7P3.0P3.1P3.2P3.3P3.4P3.5P3.6P3.7P2.7P2.6P2.5P2.4P2.3P2.2P2.1P2.0XTAL2XTAL1RSTEAALEPSENRXD/TXD/INT0/INT1/T0/T1/WR/RD/第一功能第二功能第二功能信號名稱P3.0RXD串行數(shù)據(jù)接收P3.1TXD串行數(shù)據(jù)發(fā)送P3.2外部中斷0申請P3.3外部中斷1申請P3.4T0定時/計數(shù)器0的外部輸入P3.5T1定時/計數(shù)器1的外部輸入P3.6外部RAM或外部I/O寫選通P3.7外部RAM或外部I/O讀選通P3口各引腳的第二功能12345678910111213141516171819204039383736353433323130292827262524232221VCCGNDP1.0P1.1P1.2P1.3P1.4P1.5P1.6P1.7P0.0P0.1P0.2P0.3P0.4P0.5P0.6P0.7P3.0P3.1P3.2P3.3P3.4P3.5P3.6P3.7P2.7P2.6P2.5P2.4P2.3P2.2P2.1P2.0XTAL2XTAL1RSTEAALEPSENRXD/TXD/INT0/INT1/T0/T1/WR/R